Proving 51% Amateur Built

[Xenos 59]

Did any of you use the FAA "Amateur-Built Fabrication and Assembly Checklist" when getting your aircraft inspected? Or is having good build logs and photos sufficient evidence?

https://www.faa.gov/aircraft/gen_av/ult ... listFW.pdf

[Sonerai13]

The answer to your question depends on the project and who built it. First and foremost, a thorough builder log will be required regardless of whether a checklist if filled out or not. You need the builder log to support what you've put on the checklist. The checklist can never stand on its own.

Now, referring specifically to a Sonex product, if the builder(s) didn't hire any professional assistance and have a well documented build, there would be no need to fill out the checklist. The checklist is only required if there was some level of professional assistance hired to help complete the project. I just did a certification a while ago on an aircraft (not a Sonex product) that was built using professional assistance. The checklist was used and compared against the builder log to verify that the amateur builder had still accomplished enough tasks to qualify for the airworthiness certificate. (In this case, the builder just made it.)

So don't discount the need for a substantial builder log. Regardless of whether the checklist comes into play, you'll need the construction records. But if you hire professional assistance to help complete tasks that are listed on the checklist, then you'll need to complete the checklist as well.

[radfordc]

Also, the FAA has a list of kits that it has already determined meet the 51% rule as long as the builder (or builders) don't use any commercial assistance. Sonex kits have all been approved by the FAA. If you build from a kit that isn't on the pre-approved list then you do need to prove that you meet the 51% rule and the fabrication check list is the best way to do this.

[Rynoth]

Here is a link to the Sonex website with their checklists, as well as the "letter of elegibility" showing that the FAA has already approved these particular kits per the 51% rule. Basically, if YOU built the plane from one of these kits, you've met the 51% rule. Just need a builder log to prove it was you.

https://www.sonexaircraft.com/aircraft-certification/

I printed out the checklist and letter of eligibility for my kit in case the inspector wanted to see them, but IIRC it was a non-issue as he was already aware that it was an approved kit.

Also of note is this statement at the bottom of the checklist:

"► The applicants completion of tasks can be documented in a number of ways and may include
(1) Builder’s logs.
(2) Photographs/video/DVD.
(3) Drawings.
(4) Engineering data when necessary.
(5) Relevant documentation (e.g., plans) and references (e.g., handbooks) used.
(6) Documentation concerning any commercial assist
(7) Documentation concerning any non-commercial assistance used.
(8) Part inventories and histories.
(9) Receipts, Catalogs.
(10) Log book entries"

[Xenos 59]

Perfect! Thanks so much for the info gentlemen :)

[Area 51%]

On one of the forms we're filling out for the registration it asks for; manufacturer-model-serial number of the installed engine.

Think Aerovee…..ish. What are the answers?

[Rynoth]

On one of the forms we're filling out for the registration it asks for; manufacturer-model-serial number of the installed engine.

Think Aerovee…..ish. What are the answers?

For mine, I used my last name as Manufacturer, Model Aerovee (Turbo), S/N is the serial number on the engine (it's printed on the accessory plate if it's an Aerovee.)

[Sonerai13]

On one of the forms we're filling out for the registration it asks for; manufacturer-model-serial number of the installed engine.

Think Aerovee…..ish. What are the answers?

For mine, I used my last name as Manufacturer, Model Aerovee (Turbo), S/N is the serial number on the engine (it's printed on the accessory plate if it's an Aerovee.)

That works. Or you can use AeroVee for make, 2.1 for model (or 2180), and the serial number off the accessory plate. Easy Peasy!

[radfordc]

Basically, if YOU built the plane from one of these kits, you've met the 51% rule. Just need a builder log to prove it was you.

And it doesn't even have to be just "you". There can be any number of builders as long as they are all building for "education and recreation". You can buy a project started by someone else and you're still legal for the 51% rule.

[radfordc]

The manufacturer is generally, almost always, the person who built the plane. Model/Serial number can be anything you want it to be....for example "Joe Smith Sonex SN 001".